Abrasive article and method of making the same



Aug. 21, 1934. R. c. BENNER 1,970,335

ABRASIVE ARTICLE AND MET-HOD OF MAKING THE SAME Filed Jan. 51, 1931 INVENTOR RAYMOND G. BENNER ATTORNEY Patented Aug. 21, 1934 v cNn-msmnrare-NT ol-"r ce I ABRASIvE'ARTrcLI-J AND METHOD or 1 ammo 'rnnsAMs BennenfNiagara'Falls, 'N.-Y.-, as- .signor to The "Carborundum, Company, Ni-

' I agara..l alls,'N. Y.,' a corporation or Pennsylvania Application January 31, 1931, Serial No. 512,611" K v In Canada October 2, 1930 4Claim5. (01; 51209) This invention relates to new and improved abrasive articles and to a new and improved method of joining abrasive elements to another material. The present specification is a com- 5 tinuation in part of my copending application,

Serial No. 466,089, filed July 7, 1930.

It has been desired to secure a resilient bond that adheres to the abrasive granules for attaching bonded abrasives to backing materials such as metals, wood, fibre, cloth or papenbut soft rubber does not adhere to the abrasive ma-= terialwith sumcient tenacity to provide an article even moderately satisfactory.

' I have found that this lack of adhesiveness may be obviated and that resilient and flexible abrasive articles that are water-proof can be made by the use of a bonding material containing at least a portion of an isomer of rubber that is less unsaturated chemically than is normally the case with rubber. A bond of this nature is particularly well suited for the purpose of joining bonded abrasive articles to metal backs because it absorbs the shocks incident to the grinding operation and thereby prolongs the life of abrasive articles so as used by virtue of its elasticity. It also provides suificient elasticity to compensate for the difierent rates of thermal expansion of the bonded abrasive material and the backing metal, whereby the stresses that normally would be set up in the bonded abrasive because of these different rates or expansion are eliminated or at least are reduced to a point where breakage of the bonded abrasive is avoided; thus, instead of the rapidly expanding metal backing pulling the bonded-abreamaterial is used to join the two, it stretches; the joint material and little or no pull'is'exertedupon the bonded abrasive.

I altering the proportion of isomer of rubber'used in connection with other ingredients of the bonding material, or by using materials of" difierent' characteristics along with the isomer of rubber.

When a mass of rubber is intimately mixedwith organic sulphonyl chlorides, organic sulphonic acids, sulphuric acid or mixtures thereof, or with materials that yield free sulphonic acid when heated'in the presence of rubber and then subjected to heat, an exothermic reaction takes place that converts the rubber into a product that has Bethe-same carbon and hydrogen ratio as'rllbber decreasing toughness.

sire along with it, as it does when a non-yielding,

I haveiound too, that the degree of resiliency and flexibility may be controlled over "a wide range of values by using isomers ofrubber'oi different degrees of chemical .unsaturatiom-by' liquid resin into the r (05118) x but which is chemically less unsaturated than rubber.

The degree of saturation depends to a large extent upon the proportion of'reactive material used with the rubber, although it also is influencedby 5 the temperature to which the material is subjected; For example, the resulting isomer of rubber may be 25 per cent to 67 per cent unsaturated as compared with rubber, depending upon the quantity of p-phenol sulionic acidaddeci to a given quantity of rubber A tough, balata-like product of approximately 67 per cent unsaturation, as compared with rubber, results when "7 parts of p-phenol sulionic acid are mixed with 100 parts of undissolved rubber and heated to 120 79 degrees to 145 degrees centigrade for l to 10 hours. On the other hand, a mixture of 15 parts p -phenol sulionic acid and 100 parts of undissolved rubber, when heated to 14.0 degrees centigrade for 8 hours, undergoes an exothermic reaction that raises the temperature of the mass to a temperature of the. order of magnitude of 250 degrees centigrade and results in a hard, brittle, shellaclike rubber derivative of approximately 25 per cent un'saturation as compared with rubber. By 3% the use of combinations of the above mentioned products in different proportions, there results a series of products or increasing hardness and This series of products gives rise to an unprecedented choice'in the material for use in attaching. abrasive elements to another material.

Another method by which a modifiedrubber having characteristics particularly desired for joining a bondedabrasive article'to a metal mem 99 her when the abrasive is to be used in dry grinding comprises the formation of aplastic rubber compound containing a liquid resinous material that is heat. hardenable. Oneway in which such a product may bemade comprises workinga liquid phenolic condensation resin into rubber and inverting thephasesso that the liquid resin is the continuousphase, and the rubber is the dispersed phase. There are var'iousways of working the out the addition .of sulphur, are Jharden'able by. 11 1 heat or'heat and pressure,

V bbenbut it has been found 100 to be expedient to'break down the crude rubber inakneadertype or mixer and gradually add the backing material comprises an intimate mixture I 7 ct rubber, an isomer oi rubber and sulphur in the following approximate proportions. Pm

I V weigh Rubber isomer Rubber I 1 s- Sulphur j 0.9 The ratio oi rubber isomer to rubber may decreased to provide greater resiliency.

. Another example comprises anintima te mix-' ture oi an isomer of rubber and'a'resinous material' (such as a phenolic condensation'resin) in the approximate ratio oi loparts (by weight) of isomer to:.15 parts (by weight) oi rcsinousmaterial.. 1

One iormoi finished article is illustrated by the accompanying drawing in which:

Figure 1 is a perspective view showing a steel back with an abrasive disk mounted thereon; and

Figure 2 ma cross-sectional view along the line IIII otFlgure 1. v

Injoining a bonded abrasive element to a sup- 1,970,835? Mn'rnon or MAKING Joined to thesaid bonded plate 1 shown in 1"igures1and2,Iflrst tchorsand-blastthe" one coated surface in contact with the other and cure the joint material under a pressure oi approximately 50 pounds per square inch and a temperature or 285 degrees Fahrenheit.

While I have used specific examples to illustrate methods oi attaching abrasive elements to backing materials, my invention is not limited to such examples but may be practised as defined by the appended claims.

What I claim is: I

1. An abrasive article comprising a bonded abrasive article and a metal backing member joined to said bonded abrasive article by an adhesive containing a mixture oi rubber,,an isomer oi rubber and a synthetic resin.

2. An adhesive for joining an abrasive article to a backing member, said adhesive containing a mixture of rubber, an isomer'oi rubber and a synthetic resin.

3. An abrasive article comprising a bonded abrasive article and a metal backing member abrasive article by an adhesive mixture comprising soft rubber and a synthetic resin.

4. An adhesive for joining an abrasive article to a backing member, comprising soft rubber and a synthetic resin.

RAYMOND C. BENNER.

DISCLAIMER ymomi 0. Banner, Niagara Falls,

THE SAME.

N. Y. ABBABIVE Aa'rrcnn an Patent dated August 21, 1934. Disclaimer filed January 15, 1937, by the assignee, The Oarbomndum Company.

Hereby disclaims from claim 4 an thetic resm except as such adhesive is e abrasive artlcle to a rigid backingmember;

adhesive comprising soft rubber and a synmployed for joining a preformed bonded Thereby disclaiming an adhesive per .96 comprising soft rubber and a synthetic resin, and

Y and arigid backing member joined to claim 4 to the combination of a preformed bonded abrasive'article sai bonded abrasive article by an adhesive i comgrisiasoft rubber and a synthetic resin.

zette February 9, 1987.]

backing material comprises an intimate mixture I 7 ct rubber, an isomer oi rubber and sulphur in the following approximate proportions. Pm

I V weigh Rubber isomer Rubber I 1 s- Sulphur j 0.9 The ratio oi rubber isomer to rubber may decreased to provide greater resiliency.

. Another example comprises anintima te mix-' ture oi an isomer of rubber and'a'resinous material' (such as a phenolic condensation'resin) in the approximate ratio oi loparts (by weight) of isomer to:.15 parts (by weight) oi rcsinousmaterial.. 1

One iormoi finished article is illustrated by the accompanying drawing in which:

Figure 1 is a perspective view showing a steel back with an abrasive disk mounted thereon; and

Figure 2 ma cross-sectional view along the line IIII otFlgure 1. v

Injoining a bonded abrasive element to a sup- 1,970,835? Mn'rnon or MAKING Joined to thesaid bonded plate 1 shown in 1"igures1and2,Iflrst tchorsand-blastthe" one coated surface in contact with the other and cure the joint material under a pressure oi approximately 50 pounds per square inch and a temperature or 285 degrees Fahrenheit.

While I have used specific examples to illustrate methods oi attaching abrasive elements to backing materials, my invention is not limited to such examples but may be practised as defined by the appended claims.

What I claim is: I

1. An abrasive article comprising a bonded abrasive article and a metal backing member joined to said bonded abrasive article by an adhesive containing a mixture oi rubber,,an isomer oi rubber and a synthetic resin.

2. An adhesive for joining an abrasive article to a backing member, said adhesive containing a mixture of rubber, an isomer'oi rubber and a synthetic resin.

3. An abrasive article comprising a bonded abrasive article and a metal backing member abrasive article by an adhesive mixture comprising soft rubber and a synthetic resin.

4. An adhesive for joining an abrasive article to a backing member, comprising soft rubber and a synthetic resin.

RAYMOND C. BENNER.

DISCLAIMER ymomi 0. Banner, Niagara Falls,

THE SAME.

N. Y. ABBABIVE Aa'rrcnn an Patent dated August 21, 1934. Disclaimer filed January 15, 1937, by the assignee, The Oarbomndum Company.

Hereby disclaims from claim 4 an thetic resm except as such adhesive is e abrasive artlcle to a rigid backingmember;

adhesive comprising soft rubber and a synmployed for joining a preformed bonded Thereby disclaiming an adhesive per .96 comprising soft rubber and a synthetic resin, and

Y and arigid backing member joined to claim 4 to the combination of a preformed bonded abrasive'article sai bonded abrasive article by an adhesive i comgrisiasoft rubber and a synthetic resin.

zette February 9, 1987.] 

